The types of pumps and disc-cutters to which the present application is directed are described in detail in my U.S. Pat. No. 4,170,079. In the dredge there described, a vertical boom is provided, and cutter-discs are mounted on axes of rotation parallel to the long axis of the boom, so that the plane of the discs is substantially parallel with the surface of the liquid on which the dredge is floating, and perpendicular to the long axis of the boom. In this configuration, the discs can be rotated in either direction, provided the cutters are symmetrical. Such disc-cutters were not considered adaptable to booms that were pivoted for a rather shallow angle with respect to the surface of liquid on which the dredge floated.
It has been found that by mounting the disc-cutters with certain orientation with respect both to the long axis of the boom and the surface of the liquid on which the dredge is floating, excellent results can be obtained with the disc-cutters oriented in a generally vertical direction as distinguished from the horizontal direction of the prior art.
One of the objects of this invention is to provide a dredge of the type in which a boom extends at an angle from the vertical with an improved cutter arrangement that is simple to manufacture and use and admits of the use of the same type of disc-cutter as is described in my U.S. Pat. No. 4,170,079.
Other objects will become apparent to those skilled in the art in the light of the following description and accompanying drawing.